1. Field of the Invention
The present invention relates to a wireless local area network (LAN), specifically, to a method of moving a station in a wireless LAN, in which, when a station moves from a communication area having an access point to another communication area having an access point, information about the access points of a communication area where the station was located is transmitted to the access points of a communication are to which the station will move, to thereby perform smooth communication with the moved station.
2. Discussion of Related Art
A wireless LAN, generally, includes a plurality of access points APa and APb, and a plurality of stations ST1 to ST6. Access points APa and APb are connected to each other through a wire network, and they make an interface with stations ST1 to ST6 through a radio channel of common air interface (CAI). When communication is carried out for transmitting or receiving data, stations ST1 to ST6 make an interface with access points APa and APb through the CAI, and access points APa and APb are communicated with stations ST1 to ST6 through the radio channel, thereby transmitting and receiving data. Access points APa and APb transmit data received from the stations to each other through the CAI, and transmit the data, received through the wire network, to the stations by way of the radio channel.
FIG. 2 shows the configuration of stations ST1 to ST6 and access points APa and APb. Referring to FIG. 2, each station 20 includes: a station controller 21 for processing and controlling the internal signal of the station; a CAI 22 for transmitting information to access point 30; a storage 23 for storing connection information; and a terminal interface 24 for interfacing a connection signal between terminals. Access point 30 includes: an access point controller 31 for processing and controlling the signal of the access point; an access point CAI 32 for interfacing with information transmitted from station 20; an access point storage 33 having an area where connection cancellation and connection registration station lists are stored, and destination information about corresponding station is recorded; and a wire LAN interface 34 for interfacing with other access points.
When stations ST1 to ST6 move in this wireless LAN, communication with a moved station is performed using radio channel CAI 22 shown in FIG. 2. That is, access points APa and APb are physically connected to the wire network, and interface the communication between the stations located in communication areas CA1 and CA2 which are managed by them. Otherwise, the access points transmit/receive data to/from each other through the wire network, to interface the communication between the stations located in other communication areas CA1 and CA2.
In the aforementioned wireless LAN, when station ST1 located in communication area CA1 moves to communication area CA2, for example, the station movement is performed using the method shown in FIG. 3. That is, when station ST1 moves from communication area CA1 to communication area CA2, if station ST1 requires first access point APa to cancel the connection with the station by way of CAI 22 (S10), first access point APa deletes station ST1 on a connection station list stored in its storage 33 (S11). If station ST1 requires second access point APb to be connected thereto (S12), second access point APb registers station ST1 in the connection station list stored in its storage (S13). By doing so, the station movement is completed.
When station ST1 moves from first communication area CA1 to second communication area CA2 in the above-described manner, first access point APa does not know the communication area to which station ST1 moved, even if it recognizes the movement of station ST1. Accordingly, other stations ST2 and ST3 located in communication area CA1, which were communicated with station ST1, cannot be communicated with station ST1 any more.